Replacement circulation pump.

Thomps0990

Hello all,
I’m here looking for a expierenced/ professional opinion regarding the replacement of a circulation pump.

Recently my home hydronic circulation pump Grundfos up26-99bf has started to sound extremely loud and as if there are quite a few marbles rolling around inside of it.

I’ve contacted a local supplier and they can’t seem to find a direct replacement.
My home is small, a 958 sq/ft slab on grade bungalow. 3 heating zone loops, 1/2 pex is whats in the slab. Water is heated via Bradford white combi unit.

It seems there are a ton of replacement pumps and I’m curious if it is possible for me to replace my pump with a different one if the supplier cannot find a direct replacement. Thanks in advance, let me know if there is any additional information that may be required to spec a proper pump.

Gordy

That's because it's a bronze pump, and discontinued. The replacement is a 26-99 stainless steel. Pricey.

You have an open system so you must use a non ferrous pump.

The gravel sound could be air in the system.

Gordy

That pump can be cross referenced to different brands. Taco Bell and gossett, Armstrong. They are all pretty expensive.

http://www.pumpgroup.co.uk/wp-content/uploads/LLCRC001-_0309_Cross_Reference.pdf

hot_rod

How old is the CombiCor? It sounds like a lot of pump for 3 loops? What is the pressure on the systems?

The early Combis had a small diameter coil with a bit of pressure drop, just to make sure that is the correct circulator.

SteveSan

You can use the Taco 0011-SF4 as a replacement. Flange to flange dims are 6 1/2". Any questions please call into Taco tech Support 401-942-8000 we are here Mon-Fri 8am-5pm EST.

Thomps0990

Hey guys thanks for the reply’s!

Combi is 6 months old, bought house. Researched the radiant and determined the coil inside was compromised after pressure testing radiant closed loop.
It kept getting re-pressured from the dom city side @60 psi.
So we bought a new combi and everything has been well and now heating loop is @ about 12 psi. I was just wondering if I could get away with a less hp pump as they seem to be quite a bit less expensive. I will also try and bleed some air if that could be a problem

hot_rod

I'm guessing for that size home your loops a 300' long. So yes you could go with a much smaller pump. Those new CombiCors tanks have a 1" diameter coil, virtually no pressure drop at the 1.5 or so gpm you are flowing.

Look for a multispeed or a variable speed ECM type. If you like that brand, look for a Grundfos 15-55 Alpha, or many other brands with the equivalent size and performance.

The early CombiCor tanks did require a high head circ like you have they had a long small diameter coil inside.

Jamie Hall

Sorry, but the horsepower of the pump is governed by the resistance of the heating circuit -- not the static pressure. However, to avoid an early death of the new pump, make sure that all the air is out of the system -- and make sure that the pump is pumping away from the expansion tank, if you have one, and the location of the pressure reducing valve -- both of which should be reasonably close to, but not right at, the inlet to the pump.

Thomps0990

Wow, you guys are awesome here!

I do not have an expansion tank on my system currently, I’ve been told I need one.


So I’ve found a different pump I’m going to link, considerably cheaper and potentially installed simply with similar spacing and flanges etc.

https://www.kijiji.ca/v-heating-cooling-air/north-bay/new-grundfos-home-heating-circ-pump/1324196186?utm_campaign=socialbuttons&utm_content=app_ios&utm_medium=social&utm_source=ios_social

If I can get the go ahed from you guys I think I will go this route.

SuperTech

> @Thomps0990 said:
> Wow, you guys are awesome here!
>
> I do not have an expansion tank on my system currently, I’ve been told I need one.
>
>
> So I’ve found a different pump I’m going to link, considerably cheaper and potentially installed simply with similar spacing and flanges etc.
>
> https://www.kijiji.ca/v-heating-cooling-air/north-bay/new-grundfos-home-heating-circ-pump/1324196186?utm_campaign=socialbuttons&utm_content=app_ios&utm_medium=social&utm_source=ios_social
>
> If I can get the go ahed from you guys I think I will go this route.
>

You cannot use a cast iron pump on an open system. It's against code and just a bad idea. You should consider something like a stainless steel Alpha, you're going to need to spend some money so you might as well get something quality.
I would research some of the issues with having an open system, there's several drawbacks. I wouldn't want one in my house.

Is it possible for you to post pictures of the boiler and the near boiler piping?

Gordy

Actually you should not need a stainless or bronze pump. The heating side is isolated from the domestic side. Sometime when that original bronze circulator was on there it was an open system, or the guy didn't know you didn't need a bronze pump.

Also the x tank should be on the heating side, and IF there is a back flow preventor on your domestic water main coming into the house there should be another x tank on the domestic side.

Thomps0990

Thanks for the replies one again guys!

Like I said before, 100% a closed loop system separate from the domestic side since I replaced the combi heater. Heating side is at 12 psi
Dom side is 60 psi.

Also currently the only backflip preventer is in front of the fast fill pressure regulator on the return side.
Any comments on the pump I linked?

Currently no x tank in play but this is a bridge I would like to cross after I sort out my pump issues

Zman

No time like now to add the expansion tank.
The Alpha is a nice product.
I think the Taco Veridian 1816 would be worth a look as well. Taco tech support frequents this site. If it doesn't work you can expect a quick answer to your question.

hot_rod

Thomps0990 said:

Thanks for the replies one again guys!



Like I said before, 100% a closed loop system separate from the domestic side since I replaced the combi heater. Heating side is at 12 psi

Dom side is 60 psi.



Also currently the only backflip preventer is in front of the fast fill pressure regulator on the return side.

Any comments on the pump I linked?



Currently no x tank in play but this is a bridge I would like to cross after I sort out my pump issues

From the info you presented that 15-58 should do the job. The 26-99 or equivalent would be way over sized and cause noise and wear problems, no doubt.